DIDELPHIS HUNTERI. 265 



ovarium, and upon the inner edge of this is the fimbria. The ovarium 

 is a flat, dark-coloured body 1 . 



Quaere, As there are two vaginas, in the female, at the upper part of 

 the common vagina which go in a particular manner to the uterus, 

 does the forked penis in the male suit these, and does the stream of 

 semen divide, and then go along the groove of each fork, as in a fowl ? 



Within the pouch or false belly are the nipples, six in number, three 

 on each side 2 . There is a bag at each side of the anus, placed beyond 

 the bones of the pelvis, the rectum extending farther on under the tail. 

 It contains two kinds of matter ; one a fluid, the other a kind of sedi- 

 ment which seems not soluble in the other. These bags open by small 

 ducts just at the yerge of the anus, where the rectum terminates in the 

 skin. 



An Opossum [Didelphis Hunteri, Waterhouse 3 ] . 



This animal is of the size of a small rat, but is brown, like a mouse. 

 Its head terminates on all sides equally to the tip of the nose : its fore- 

 feet are those of a rat, mouse, &c, but the great toe of the hind-foot is 

 a thumb, as in the monkey, or large opossum. Its tail is not so long 

 as the rat's, but is stronger, and does not taper to the end so gradually, 

 terminating in a pretty thick end : its motion is a flexion of the under- 

 side, so as to throw itself into spirals for clasping. The hair is much 

 longer on the upper surface of the tail than the under surface. It has 

 seven nipples situated on the lower part of the belly; not so much 

 between the thighs as in the cow, mare, &c. ; six of these nipples are as 

 it were set in a circle, and the seventh is in the centre of the whole. 

 Prom the size of the nipples it is probable she had had young very 

 lately, but there was no appearance of a pouch. 



The oesophagus is about half an inch long below the diaphragm. 

 The stomach is a roundish pouch, having a very short small end, so that 

 the pylorus is very near the oesophagus. The duodenum passes to the 

 right and then down, having a mesentery : it becomes more fixed to the 

 back, and then loose, forming jejunum and ileum, both of which are 

 but short. The mesentery is pretty loose and narrow. The ileum 

 passes into the caecum upon the right, and pretty high up ; the caecum 

 is similar to the large opossum's. The colon passes almost immediately 



1 [Hunt. Preps. Nos. 2735 — 2738, and No. 2738 A, the description of which supplies 

 the answer to the question that follows in the text. — Physiol. Catai. vol. iv. p. 154.] 



2 [The Hunterian Preparation, Physiol. Series, No. 3795 {Didelphis opossum, 

 Linn.), shows seven nipples, one in the centre and three on each side. — Physiol. 

 Catal. vol. v. p. 210.] 



3 [The specimen is preserved in spirits in the Natural History Series of the 

 Hunterian Collection. See ' Naturalists' Library,' vol. xi. p. 110.] 



